Figure 4a shows the global embedding; Figure 4b shows pancreatic islets of either normal or type 2 diabetes mellitus status. This disease primarily separates from normal cells in β- and α-cell regions—these are the principal endocrine populations that secrete insulin and glucagon, respectively. We overlaid gradients of the insulin output (Ins1) in this PCA, and notice how an increase in insulin relates to disease → healthy. The gene discussed is GCG; the disease is diabetes mellitus.